Automatic roller band filter

ABSTRACT

IN AUTOMATIC ROLLER BAND FILTER ASSEMBLIES OF THE TYPE IN WHICH A FILTER BAND WOUND ON A FREELY-ROTATABLE BOBBIN IN AN UPPER PORTION IS PULLED DOWN THROUGH A FILTERING INTERMEDIATE PORTION BY A DRIVEN BOBBIN MOUNTED IN A LOWER PORTION, A PROBLEM EXISTS IS ENSURING THAT AN ADEQUATE SEAL IS PROVIDED AT THE EDGES OF THE FILTER BAND DURING ITS DOWNWARD TRAVEL THROUGH THE INTERMEDIATE ZONE. THIS IS PROVIDED ACCORDING TO THE INVENTION BY THE PROVISION OF GIRDER-SHAPED MEMBERS EXTENDING FROM THE UPPER TO THE LOWER PORTIONS IN ASSOCIATION WITH A RIGHT-ANGLED PRESSURE PLATE MOUNTED ON THE SAID GIRDER MEMBER WHEREBY A SEALING SURFACE OF THE SAID SEALING MEMBER MAY BE MOVED ONTO THE FILTER BAND PASSING OVER THE SAID GIRDERSHAPED MEMBERS. IN A PARTICULAR EMBODIMENT OF THE INVENTION THE SAME GIRDER-SHAPED MEMBERS ARE HAT-SHAPED MEMBERS, AND THE RIGHT-ANGLED SEALING MEMBERS ARE MOUNTED TO ENGAGE IN SLOTS IN THE GIRDER MEMBERS TO ALLOW THE SAID MOVEMENT TO AND FROM A SEALING POSITION.

United States Patent Office Int. Cl. B1d 46/18 US. Cl. 55-354 3 Claims ABSTRACT OF THE DISCLOSURE In automatic roller band filter assemblies of the type in which a filter band wound on a freely-rotatable bobbin in an upper portion is pulled down through a filtering intermediate portion by a driven bobbin mounted in a lower portion, a problem exists in ensuring that an adequate seal is provided at the edges of the filter band during its downward travel through the intermediate zone. This is provided according to the invention by the provision of girder-shaped members extending from the upper to the lower portions in association with a right-angled pressure plate mounted on the said girder member whereby a sealing surface of the said sealing member may be moved onto the filter band passing over the said girdershaped members. In a particular embodiment of the invention the said girder-shaped members are hat-shaped members, and the right-angled sealing members are mounted to engage in slots in the girder members to allow the said movement to and from a sealing position.

This invention relates to an automatic roller band filter assembly, and particularly relates to such filter assemblies comprising an upper portion having a filter band roll of glass fibre or textile freely rotatably mounted therein, and a lower portion having a driven roller (i.e. bobbin) for drawing the filter band off the upper roll across a sealed and filtering intermediate portion of the filter assembly. The component comprising the said bottom, intermediate and upper portions are generally assembled on site and built into an opening in a brick wall or in an air ventilation duct. I

From time to time a fresh roll of filter band is inserted into the upper portion of the filter assembly, the fully wound roll being removed from the lower portion. This exchange should be capable of being performed as quickly as possible. This means that the said rolls must be easily exchangeable, that the intermediate portion must be appropriately constructed, and more particularly that the said intermediate portion must constitute the loadbearing member connecting the lower with the upper portion. In the intermediate portion the filter band is supported and guided by backing members across the flat faces of the band, the arrangement besides being simple must form a seal between the band and the frame of the roller band filter.

According to the invention these objects are achieved in an automatic roller band filter assembly, comprising an upper portion, a lower portion and an intermediate filter portion; a roll of filter band on a bobbin freely rotatably mounted in the said upper portion; a driven bobbin rotatably mounted in the said lower portion and adapted to receive filter band from the said upper portion after passing through the said intermediate filter portion; a girder-shaped member on each side of the said assembly extending from and attached to the said upper portion and the said lower portion; and a right-angled pressure plate adjustably mounted on each of the said girdershaped members whereby a sealing suruface of the said pressure plates may be moved to and from a sealing posi- 3,616,620 Patented Nov. 2., 1971 tion on the edge of a filter band passing between the said surface and a surface of the said girder-shaped member.

By this arrangement the simple pressure plates provide a sufliciently tight seal, and also permit a fresh filter band to be easily inserted.

The said girder-shaped members extending between the said upper and lower portions preferably are hat-shaped sections, and the said sealing plates are preferably attached thereto by butterfly nut and bolts engaged in slots in the said hat-shaped sections to achieve the required sealing adjustment.

An embodiment of the invention is hereinafter described and illustrated in the accompanying drawings, of which FIG. 1 is a perspective view of a roller band filter assembly,

FIG. 2 is a horizontal cross-section taken substantially along the line 2-2 of FIG. 1 showing the shape of the side members of the said assembly, and

FIG. 3 is a fragmentary side elevation view of FIG. 2.

Referring to FIG. 1, the roller band filter assembly comprises an upper portion 1, an intermediate portion 2 and a lower portion 3. A filter band roll (not visible in FIG. 1) is wound on a freely rotatable bobbin (not shown) in the upper portion 1. During use the filter band is wound off the said freely rotatable bobbin and is drawn across the intermediate filtering portion 2 and is finally Wound on a driven bobbin 4 in the lower portion 3. In the intermediate portion 2 the dust removed from the dust-laden air is deposited on clean filter cloth pulled off from the upper bobbin, the dirty filter band being wound onto the bottom bobbin 4. After a given period of time the empty upper bobbin is replaced by a full bobbin, and the bobbin 4 at the bottom carrying the dirty cloth is removed.

For directly driving the driven bobbin 4, a motor 5 with gearing and bearing means 6 is provided which is secured to theframe member 7 of the lower portion 3. The other bearing 8 of the driven bobbin 4 is located on the corresponding frame member 9 on the other side of the frame.

The load-bearing connection between the upper portion 1 which carries the hingeably raisable cover 10 concealing the upper roll and the lower portion 3 consists of two hat-shaped sections 11 forming side members which at each end carry plates 12. The term hat-shaped is intended to indicate in a concise manner the special crosssectional form of the girders 11. This form shows best in FIG. 2 where the girders 11 can be seen to be shaped like a mans straw skimmer or boater with an extension. By means of these plates the side members are connected to the lower portion 3 and to the upper portion 1 respectively. The sections 11 contain slot-shaped holes 13 for the passage therethrough of bolts with wing nuts 14 for attaching right-angled press-on sections 15 to the side members. The slot-shaped holes 13 permit the distance 16 between the section 15 and the section 11 to be preadjusted to the thickness of the filter band.

The edges of the filter band which is not itself shown in the drawings travel in the gaps 16 and are thus kept in sealing contact with the sections 11 of the frame of the roller band filter assembly. For the insertion of a fresh band the gap 16 can be widened by slackening the wing nuts 14 and displacing the section 15 sufiiciently for the fresh filter band to be passed down the intermediate portion 2 with ease.

In the region of the intermediate portion 2 where the actual filtering action takes place, the edges of the filter band travel in sealing contact between the two sections 15 and 11 and between the backing struts 17 which face the front and the back of the band. The band from the upper Nov. 2,1971 G. M. NEUMANN 3,616,620

AUTOMATIC ROLLER BAND FILTER Filed Dec. 30, 1968 In ventor: e grhfl d Max Neu Mm 

